英文文献科技类原文及翻译 64

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科技文献中英文对照翻译

Sensing Human Activity:GPS Tracking感应人类活动:GPS跟踪Stefan van der Spek1,*,Jeroen van Schaick1,Peter de Bois1,2and Remco de Haan1Abstract:The enhancement of GPS technology enables the use of GPS devices not only as navigation and orientation tools,but also as instruments used to capture travelled routes:assensors that measure activity on a city scale or the regional scale.TU Delft developed aprocess and database architecture for collecting data on pedestrian movement in threeEuropean city centres,Norwich,Rouen and Koblenz,and in another experiment forcollecting activity data of13families in Almere(The Netherlands)for one week.Thequestion posed in this paper is:what is the value of GPS as‘sensor technology’measuringactivities of people?The conclusion is that GPS offers a widely useable instrument tocollect invaluable spatial-temporal data on different scales and in different settings addingnew layers of knowledge to urban studies,but the use of GPS-technology and deploymentof GPS-devices still offers significant challenges for future research.摘要：增强GPS技术支持使用GPS设备不仅作为导航和定位工具,但也为仪器用来捕捉旅行路线:作为传感器,测量活动在一个城市或区域范围内规模。

科技英语原文及简单翻译

科技英语原文及简单翻译How ASIMO WorksIntroduction to How ASIMO WorksWant a robot to cook your dinner, do your homework, clean your house, or get your groceries? Robots already do a lot of the jobs that we humans don't want to do, can't do, or simply can't do as well as our robotic counterparts.Honda engineers have been busy creating the ASIMO robot for more than 20 years. In this article, we'll find out what makes ASIMO the most advanced humanoid robot to date.The Honda Motor Company developed ASIMO, which stands for Advanced Step in Innovative Mobility, and is the most advanced humanoid robot in the world. According to the ASIMO Web site, ASIMO is the first humanoid robot in the world that can walk independently and climb stairs.Rather than building a robot that would be another toy, Honda wanted to create a robot that would be a helper for people -- a robot to help around the house, help the elderly, or help someone confined to a wheelchair or bed. ASIMO is 4 feet 3 inches (1.3 meters) high, This allows ASIMO to do the jobs it was created to do without being too big and menacing.ASIMO's Motion: Walk Like a HumanHonda researchers began by studying the legs of insects, mammals, and the motion of a mountain climber with prosthetic legs to better understand the physiology and all of the things that take place when we walk -- particularly in the joints. For example, the fact that we shift our weight using our bodies and especially our arms inorder to balance was very important in getting ASIMO's walking mechanism right. The fact that we have toes that help with our balance was also taken intoconsideration: ASIMO actually has soft projections on its feet that play a similar role to the one our toes play when we walk. This soft material also absorbs impact on the joints, just as our soft tissues do when we walk.ASIMO has hip, knee, and foot joints. Robots have joints that researchers refer to as \degrees of freedom.\A single degree of freedom allows movement either right and left or up and down. ASIMO has 34 degrees of freedom spread over different points of its body in order to allow it to move freely. There are three degrees of freedom in ASIMO's neck, seven on each arm and six on each leg. The number of degrees offreedom necessary for ASIMO's legs was decided by measuring human joint movement while walking on flat ground, climbing stairs and running.ASIMO also has a speed sensor and a gyroscope sensor mounted on its body. They perform the tasks of:? ?sensing the position of ASIMO's body and the speed at which it is moving relaying adjustments for balance to the central computer These sensors work similarly to our inner ears in the way they maintain balance and orientation.ASIMO also has floor surface sensors in its feet and six ultrasonic sensors in its midsection. These sensors enhance ASIMO's ability to interact with its environment by detecting objects around ASIMO and comparing gathered information with maps of the area stored in ASIMO's memory.To accomplish the job our muscles and skin do in sensing muscle power, pressure and joint angles, ASIMO has both joint-angle sensors and a six-axis force sensor.Unless you know a lot about robotics, you may not fully grasp the incredible milestone it is that ASIMO walks as we do. The most significant part of ASIMO's walk is the turning capabilities. Rather than having to stop and shuffle, stop and shuffle, and stop and shuffle into a new direction, ASIMO leans and smoothly turns just like a human. ASIMO can also self-adjust its steps in case it stumbles, is pushed, or otherwise encounters something that alters normal walking.In order to accomplish this, ASIMO's engineers had to find a way to work with the inertial forces created when walking. For example, the earth's gravity creates a force, as does the speed at which you walk. Those two forces are called the \inertial force.\ground, called the \posture has to work to make it happen. This is called the \zero moment point\(ZMP). To control ASIMO's posture, engineers worked on three areas of control:? ?Floor reaction control means that the soles of the feet absorb floor unevenness while still maintaining a firm stance.Target ZMP control means that when ASIMO can't stand firmly and its body begins to fall forward, it maintains position by moving its upper body in the direction opposite the impending fall. At the same time, it speeds up its walking to quickly counterbalance the fall.?Foot-planting location control kicks in when the target ZMP control has been activated. It adjusts the length of the step to regain the right relationship between the position and speed of the body and the length of the step.ASIMO's Motion: Smooth MovesASIMO can sense falling movements and react to them quickly; but ASIMO's engineers wanted more. They wanted the robot to have a smooth gait as well as do something that other robots can't do -- turn without stopping.When we walk around corners, we shift our center of gravity into the turn. ASIMO uses a technology called \predictive movement control,\Intelligent Real-Time Flexible Walking Technology or I-Walk, to accomplish that same thing. ASIMO predicts how much it should shift its center of gravity to the inside of the turn and how long that shift should be maintained. Because this technolgy works in real time, ASIMO can do this without stopping between steps, which other robots must do.Essentially, with every step ASIMO takes, it has to determine its inertia and then predict how its weight needs to be shifted for the next step in order to walk and turn smoothly. It adjusts any of the following factors in order to maintain the right position:? ? ? ?the length of its steps its body position its speedthe direction in which it is steppingWhile reproducing a human-like walk is an amazing achievement, ASIMO can now run at speeds up to 3.7 miles per hour (6 kilometers per hour). In order to qualify as a true running robot, ASIMO must have both feet off the ground for an instant in each step. ASIMO manages to be airborne for .08 seconds with each step while running. Honda engineers encountered an entirely new set of challenges while trying to give ASIMO the ability to run. They gave ASIMO’s torso a degree of freedom to aid in bending and twisting so that the robot could adjust its posture while airborne. Without this ability, ASIMOwould lose control while airborne, possibly spinning in the air or tripping when landing.In order to make turns smoothly while running, the engineers enhanced ASIMO's ability to tilt its center of gravity inside turns to maintain balance and counteractcentrifugal force. ASIMO could even anticipate turns and begin to lean into them before starting the turn, much like you would if you were skiing or skating.ASIMO如何工作介绍如何工作。

外文文献翻译原文及译文

华北电力大学毕业设计（论文）附件外文文献翻译学号： 200701000324 姓名:杨曦所在院系：电力工程系专业班级：电气化0707指导教师：安勃原文标题： Research on Smart Grid in China2011年06月20日对中国智能电网的研究1摘要——智能电网是电力系统的未来发展的新方向。

在本文中，首先是智能电网的背景，意义，以及概念和结构。

典型的智能电网图如下所示.然后,在美国和欧洲智能电网的发展现状进行了描述，并对这些国家未来发展思路的趋势进行了总结和比较及分析。

此外，分析了中国智能电网发展的必要性，详细介绍了在目前与中国与有关项目，并对特高压电网和智能电网之间的的关系进行了讨论。

最后，对智能电网在未来在中国电网的潜在作用进行了展望和并为中国的智能电网发展指明新方向.索引词,智能电网，特高压电网，规划,经营，管理一导言随着世界经济全球化的推广,石油价格一直维持在一个上升的趋势。

还值得注意的是世界范围内的的能源供应短缺，对资源和环境的压力越来越大,同时，由于目前电网的低效率，在能源输送过程中损失了巨大的电力。

此外,由于不断增长的电力需求和用户对电力可靠性和质量日益增长的要求，电力工业正面临着前所未有的挑战和机遇。

因此，一个有环境友好,经济，高性能，低投资，安全性，可靠性和灵活性特点的的电力系统一直是电力工程师的目标。

尽管如此，基础设施和先进的仪表出现互联网更广泛地的使用加速了这个过程[1］。

自1990年以来随着分布式发电越来越多地使用，已经对对电网的强度提出更多的需求和要求［2][3]。

对于这些问题，为了找出最佳的解决方案，电力公司应接受新的思路，采用新技术，对现有的能源系统进行潜力挖掘，对技术和应用加以改进。

来自不同国家的学者和专家已经达成共识：未来电网的必须能够满足不同的需求及能源发电，高度市场化的电力交易的需求，由此可以满足客户的自我选择。

所有这些都将成为未来智能电网的发展方向。

科技文献翻译

科技文献翻译Technology has transformed every aspect of our lives, from the way we communicate and work to how we shop and entertain ourselves. With the rapid advancement of technology, there is a growing demand for accurate translations of technology-related literature. This article aims to provide a translation of a technology paper consisting of 700 words.The paper titled "The Role of Artificial Intelligence in Autonomous Vehicles" explores the impact of AI in self-driving cars. Autonomous vehicles have gained significant attention in recent years due to their potential to revolutionize transportation. This paper discusses how AI technologies, such as deep learning and machine vision, have contributed to the development of autonomous vehicles.一项名为“人工智能在自动驾驶汽车中的角色”的研究探讨了AI在无人驾驶汽车中的影响。

在过去几年中，由于其改变出行方式的潜力，自动驾驶汽车引起了广泛关注。

科技文献中英文翻译

Intelligent Power Supply英文With the rapid development of electronic technology, application field of electronic system is more and more extensive, electronic equipment, there are more and more people work with electronic equipment, life is increasingly close relationship. Any electronic equipment are inseparable from reliable power supply for power requirements, they more and more is also high. Electronic equipment miniaturized and low cost in the power of light and thin,small and efficient for development direction. The traditional transistors series adjustment manostat is continuous control linear manostat. This traditional manostat technology more mature, and there has been a large number of integrated linear manostat module, has the stable performance is good, output ripple voltage small, reliable operation, etc. But usually need are bulky and heavy industrial frequency transformer and bulk and weight are big filter.In the 1950s, NASA to miniaturization, light weight as the goal, for a rocket carrying the switch power development. In almost half a century of development process, switch power because of is small volume, light weight, high efficiency, wide range, voltage advantages in electric, control, computer, and many other areas of electronic equipment has been widely used. In the 1980s, a computer is made up of all of switch power supply, the first complete computer power generation. Throughout the 1990s, switching power supply in electronics,electrical equipment, into the rapid development. In addition, large scale integrated circuit technology, and the rapid development of switch power supply with a qualitative leap, raised high frequency power products of, miniaturization, modular tide.Power switch tube, PWM controller and high-frequency transformer is an indispensable part of the switch power supply. The traditional switch power supply is normally made by using high frequency power switch tube division and the pins, such as using PWM integrated controller UC3842 + MOSFET is domestic small power switch power supply, the design method of a more popularity.Since the 1970s, emerged in many function complete integrated control circuit, switch power supply circuit increasingly simplified, working frequency enhancesunceasingly, improving efficiency, and for power miniaturization provides the broad prospect. Three end off-line pulse width modulation monolithic integrated circuit TOP (Three switch Line) will Terminal Off with power switch MOSFET PWM controller one package together, has become the mainstream of switch power lC development. Adopt TOP switch lC design switch power, can make the circuitsimplified,volume further narrowing, cost also is decreased obviousiy.Monolithic switching power supply has the monolithic integrated, the minimalist peripheral circuit, best performance index, no work frequency transformer can constitute a significant advantage switching power supply, etc. American Pl (with) company in Power in the mid 1990s first launched the new high frequency switching Power supply chip, known as the "top switch Power", with low cost, simple circuit, higher efficiency. The first generation of products launched in 1994 represented TOP100/200 series, the second generation product is the TOPSwitch - debuted in 1997 П .The above products once appeared showed strong vitality and he greatly simplifies the design of 150W following switching power supply and the development of new products for the new job, also, high efficiency and low cost switch power supply promotion and popularization created good condition, which can be widely used in instrumentation, notebook computers, mobile phones, TV, VCD and DVD, perturbation VCR, mobile phone battery chargers, power amplifier and other fields, and form various miniaturization, density, on price can compete with the linear manostat AC/DC power transformation module.Switching power supply to integrated direction of future development will be the main trend, power density will more and more big, to process requirements will increasingly high. In semiconductor devices and magnetic materials, no new breakthrough technology progress before major might find it hard to achieve, technology innovation will focus on how to improve the efficiency and focus on reducing weight. Therefore, craft level will be in the position of power supply manufacturing higher in. In addition, the application of digital control IC is the future direction of the development of a switch power. This trust in DSP for speed and anti-interference technology unceasing enhancement. As for advanced control method, now the individual feels haven't seen practicability of the method appears particularly strong, perhaps with the popularity of digital control, and there are some new control theory into switching power supply.(1) The technology: with high frequency switching frequencies increase, switchconverter volume also decrease,power density has also been boosted, dynamic response improved. Small power DC - DC converter switch frequency will rise to MHz. But as the switch frequency unceasing enhancement, switch components and passive components loss increases, high-frequency parasitic parameters and high-frequency EMI and so on the new issues will also be caused．(2) Soft switching technologies: in order to improve the efficiency of non-linearity of various soft switch, commutation technical application and hygiene, representative of soft switch technology is passive and active soft switch technology, mainly including zero voltage switch/zero current switch (ZVS/ZCS) resonance, quasi resonant, zero voltage/zero current pulse width modulation technology (ZVS/ZCS - PWM) and zero voltage transition/zero current transition pulse width modulation (PWM) ZVT/ZCT - technical, etc. By means of soft switch technology can effectively reduce switch loss and switch stress, help converter transformation efficiency.(3) Power factor correction technology (IC simplifies PFC). At present mainly divided into IC simplifies PFC technology passive and active IC simplifies PFC technology using IC simplifies PFC technology two kinds big, IG simplifies PFC technology can improve AC - DC change device input power factor, reduce the harmonic pollution of power grid.(4) Modular technology. Modular technology can meet the needs of the distributed power system, enhance the system reliability.(5) Low output voltage technology. With the continuous development of semiconductor manufacturing technology, microprocessor and portable electronic devices work more and more low, this requires future DC - DG converter can provide low output voltage to adapt microprocessor and power supply requirement of portable electronic devicesPeople in switching power supply technical fields are edge developing related power electronics device, the side of frequency conversion technology, development of switch between mutual promotion push switch power supply with more than two year growth toward light, digital small, thin, low noise and high reliability, anti-interference direction. Switching power supply can be divided into the AC/DC and DC/DC two kinds big, also have AC/AC DC/AC as inverter DC/DC converter is now realize modular, and design technology and production process at home and abroad, are mature and standardization, and has approved by users, but the AC/DC modular, because of its own characteristics in the process of making modular, meetmore complex technology and craft manufacture problems. The following two types of switch power supply respectively on the structure and properties of this.Switching power supply is the development direction of high frequency, high reliability, low consumption, low noise, anti-jamming and modular. Because light switch power, small, thin key techniques are changed, so high overseas each big switch power supply manufacturer are devoted to the development of new high intelligent synchronous rectifier, especially the improvement of secondary devices of the device, and power loss of Zn ferrite (Mn) material? By increasing scientific and technological innovation, to enhance in high frequency and larger magnetic flux density (Bs) can get high magnetic under the miniaturization of, and capacitor is a key technology. SMT technology application makes switching power supply has made considerable progress, both sides in the circuit board to ensure that decorate components of switch power supply light, small, thin. The high frequency switching power supply of the traditional PWM must innovate switch technology, to realize the ZCS ZVS, soft switch technology has become the mainstream of switch power supply technical, and greatly improve the efficiency of switch power. For high reliability index, America's switch power producers, reduce by lowering operating current measures such as junction temperature of the device, in order to reduce stress the reliability of products made greatly increased．Modularity is of the general development of switch power supply trend can be modular power component distributed power system, can be designed to N + 1 redundant system, and realize the capacity expansion parallel. According to switch power running large noise this one defect, if separate the pursuit of high frequency noise will increase its with the partial resonance, and transform circuit technology, high frequency can be realized in theory and can reduce the noise, but part of the practical application of resonant conversion technology still have a technical problem, so in this area still need to carry out a lot of work, in order to make the technology to practional utilization.Power electronic technology unceasing innovation, switch power supply industry has broad prospects for development. To speed up the development of switch power industry in China, we must walk speed of technological innovation road, combination with Chinese characteristics in the joint development path, for the high-speed development of national economy to make the contribution.中文智能开关电源随着电子技术的高速发展，电子系统的应用领域越来越广泛，电子设备的种类也越来越多，电子设备与人们的工作、生活的关系口益密切。

英语科技文翻译

Protein Filaments Caught in the Act蛋白质细丝的行为Grant J. Jensen*C ells can be thought of as little chemical processing plants, but they also 细胞可以被看做小型化工加工工厂，但他们也能完成一些了不起的物accomplish some marvelous physical and mechanical tasks such as理和机械工作，例如把自己塑造成特有的形状，朝营养素处移动，组shaping themselves into characteristic forms, moving toward nutrients, 织复杂的内部结构，复制、分离DNA。

organizing their complex interiors, replicating and then segregating their DNA, and dividing (1). It has long been understood how in 人们很早就认识到真核细胞中的大部分工作是由它的细胞骨架细丝----一种细胞eukaryotes most of this work is done by cytoskeletal filaments –long中的细丝网状或束状的长的蛋白质聚合物来担当的。

protein polymers that are used like cables, tracks, and bea ms in the machinery of the cell. But until about a decade ago, it was a 但是直到大约十年前，细菌细胞如何完成同样的工作仍是个谜团。

mystery as to how bacterial cells did the same tasks. None of the 当时任何一种科技，包括传统的电子显微学方法，都不能令人信服地existing technologies, including "traditional" electronmicroscopy在细菌细胞中发现类似的细胞骨架细丝。

经济学人科技类文章中英双语（5篇范例）

经济学人科技类文章中英双语（5篇范例）第一篇：经济学人科技类文章中英双语The Brain Activity Map绘制大脑活动地图Hard cell 棘手的细胞An ambitious project to map the brain is in the works.Possibly too ambitious 一个绘制大脑活动地图的宏伟计划正在准备当中，或许有些太宏伟了 NEWS of what protagonists hope will be America’s next big science project continues to dribble out.有关其发起人心中下一个科学大工程的新闻报道层出不穷。

A leak to the New York Times, published on February 17th, let the cat out of the bag, with a report that Barack Obama’s administration is thinking of sponsoring what will be known as the Brain Activity Map.2月17日，《纽约时报》刊登的一位线人报告终于泄露了秘密，报告称奥巴马政府正在考虑赞助将被称为“大脑活动地图”的计划。

And on March 7th several of those protagonists published a manifesto for the project in Science.3月7日，部分发起人在《科学》杂志上发表声明证实了这一计划。

The purpose of BAM is to change the scale at which the brain is understood.“大脑活动地图”计划的目标是改变人们在认知大脑时采用的度量方法。

英文文献科技类原文及翻译

本科毕业设计(论文)外文翻译姓名: 王文超学号： 200715010220专业: 电气工程及其自动化班级: 电气071502指导教师: 智泽英职称：副教授日期: 2011年6月12日电子信息工程学院The basics of Computer Numerical ControlWhile the specific intention and application for CNC machines vary from machine type toanother, all forms of CNC have common benefits. Though the thrust of this presentation is to teach you CNC usage, it helps to understand why these sophisticated machines have become so popular. Here are but a few of the more important benefits offered by CNC equipment.The first benefit offered by all forms of CNC machine tools is improved automation. The operator intervention related to producing workpieces can be reduced or eliminated. Many CNC machines can run unattended during their entire machining cycle, freeing the operator to do other tasks. This gives the CNC user several side benefits including reduced operator fatigue, fewer mistakes caused by human error, and consistent and predictable machining time for each workpiece. Since the machine will be running under program control, the skill level required of the a CNC operator (related to basic machining practice) is also reduced as compared to a machinist producing workpieces with conventional machine tools.The second major benefit of CNC technology is consistent and accurate workpieces. Today’s CNC machines boast almost unbelievable accuracy and repeatability specifications. This means that once a program is verified, two, ten, or one thousand identical workpieces can be easily produced with precision and consistency.A third benefit offered by most forms of CNC machine tools is flexibility. Since these machines are run from programs, running a different workpiece is almost as easy as loading a different program. Once a program has been verified and executed for one production run, it can be easily recalled the next time the workpiece is to be run. This leads to yet another benefit, fast change-overs. Since these machines are very easy to setup and run, and since programs can be easily loaded, they allow very short setup time. This is imperative with today’s Just-In-Time product requirements.1. Motion control-the heart of CNCThe most basic function of any CNC machine is automatic, precise, and consistent motion. Rather than applying completely mechanicaldevices to cause motion as is required on most conventional machine tools, CNC machines allow motion control in a revolutionary manner. All forms of CNC equipment have two or more directions of motion, called axes. These axes can be precisely and automatically positioned alongtheir lengths of travel. The two most common axis types are linear (driven along a straight path) and rotary (driven along a circular path).Instead of causing motion by turning cranks and handwheels as is required on conventional machine tools, CNC machines allow motions to be commanded through programmed commands. Generally speaking, the motion type (rapid, linear, and circular), the axes to move, the amount of motion and the motion rate (feedrate) are programmable with almost all CNC machine tools.Accurate positioning is accomplished by the operator counting the number of revolutions made on the handwheel plus the graduations on the dial. The drive motor is rotated a corresponding amount, which in turn drives the ball screw, causing linear motion of the axis. A feedback device confirms that the proper amount of ball screw revolutions has occurred.A CNC command executed within the control (commonly through a program) tells the drive motor to rotate a precise number of times. The rotation of the drive motor in turn rotates the ball screw. And the ball screw causes drives the linear axis. A feedback device at the opposite end of the ball screw allows the control to confirm that the commanded number of rotations has taken place.Though a rather crude analogy, the same basic linear motion can be found on a common table vise. As you rotate the vise crank, you rotate a lead screw that, in turn, drives the movable jaw on the vise. By comparison, a linear axis on a CNC machine tool is extremely precise. The number of revolutions of the axis drive motor precisely controls the amount of linear motion along the axis.How axis motion is commanded-understanding coordinate systems. It would be infeasible for the CNC user to cause axis motion by trying to tell each axis drive motor how many times to rotate in order to command a given linear motion amount. (This would be like having to figure out how many turns of the handle on a table vise will cause the movable jaw to move exactly one inch!) Instead, all CNC controls allow axis motion to be commanded in a much simpler and more logical way by utilizing some form of coordinate system. The two most popular coordinate systems used with CNC machines are the rectangular coordinate system and the polar coordinate system. By far, the move popular of these two is the rectangular coordinate system, and we’ll use it for all discussions made during this presentation.。

英文科技文献翻译

英文文献翻译二〇一二年五月三十日Integrated wiring systemModern science and technology progress has made rapid development of computer and network technology, provides a more powerful computer processing capacity and network communication ability. The computer and network communication technology can greatly improve the modern enterprise production management efficiency, reduce the operation cost, and makes the modern enterprise can obtain more effectively and timely decision market information, provide more quickly, more satisfactory service to customers, in the competition. The computer and network communication technology has become a key factor in the success of the company.Integrated cabling system in order to meet the development needs is specially designed a set of cabling system. For modern buildings, such as the body, it adopted a series of nerve of high quality standard, modular combinations of material, the voice, data and image and control signal system using uniform transmission media, through comprehensive, integrated unified planning design in a set of standard cabling system in modern architecture, the three subsystems will connect organically, and system integration for the modern architecture provides a physical medium. Structured cabling system can directly related to the success of the modernization of the building, choose a high quality of integrated wiring system is of vital importance.Computer and communication networks are dependent on wiring system as the physical basis of network connections and information transmission channel. The traditional single application on a particular special layout techniques, lack of flexibility and development of, can not meet the rapid development of modern business needs of network applications. The new generation of structured cabling systems provide the user the required data, voice, fax, video and other information service connections, which allows voice and data communications equipment, switching equipment, information management systems and equipment control system , security system connected to each other, but also to make these devices with external communication networks. It includes the building to the external network or phone line connection Bureau,with the work area of voice or data terminals associated with all the cables and wiring components. Cabling system composed by different series of components, including: transmission media, line management of hardware, connectors, sockets, plugs, adapters, transmission electronic circuits, electrical protection equipment and support. Compared with the previous wiring, cabling system features can be summarized as:Practicality: after the implementation of cabling systems will be able to adapt to the modern and future communication technology development and implementation of voice, data, unified communications, signal transmission.Flexibility: wiring system can satisfy the requirements of various applications, information points to any connection of different types of terminal equipment, such as telephone, computer, printer, computer terminal, electric machine, various sensors and image monitoring equipment.Modularity: integrated cabling system in fixed in buildings, the level of all cable connectors are basic type of the standard, all voice, data and interconnection of building automation, network and image, with convenient use, equipment, change, management and expansion.Scalability: integrated wiring system is for future expansion, more use, easy to expand into new equipment.Economy: the integrated wiring system enables managers, and at the same time, reduce the modular structure, work because of the difficulty of future changes greatly reduced the cost or moving system.General: to meet the standard of international communication and computer network topology structure, can adapt different transmission speed communication can adapt to the requirement, can support and accommodate various computer network operation.1 workspace subsystemPurpose is to realize the workspace terminal equipment and level of connections between subsystems, the terminal devices connected to the information socket connection cables. Workspace used computer, networkequipment is distributed (on), telephone, or may alarm detector, camera, monitors, acoustics, etc.2 Horizontal subsystemPurpose is to realize information socket and management subsystem (jumper wire connection between frame), will lead to the management subsystem of user workspace, and to provide users with one accord with international standard pronunciation, satisfy the requirements and the high-speed data transmission information points. The subsystem of information from a job, decorate the socket to the inside of the administrative levels of the cable distribution frames. In the system of transmission medium of UTP (4) shielding twisted-pair cable, it can support the most modern communication equipment. If you need some broadband application, you can use fiber. Information ISDN8 for export by core RJ45 jack (standard), each information socket outlets can be flexibly according to actual application requirements and optional change purposes.3 the management subsystemThis sub-system connected by a cross, composed of interconnect patch panel. Management point of connection means to connect to other subsystems. Cross-connect and interconnect allows communication lines locate or relocate to different parts of the building to make it easier to manage communication lines, so that when the mobile terminal device easily plug. Interconnection distribution frame connections under different hardware sub-floor distribution frame (box) IDF and MDF (box) MDF, IDF can be installed on each floor of the trunk connection between, MDF is usually installed in the equipment room.4 vertical lines subsystemPurpose is to achieve the computer equipment, pabx (PBX), with the management subsystem of control center is building a connection between the main cable, routing. This is usually between two units subsystem, especially in the central point in the public system provides more line facilities. By building the system all vertical lines and more logarithmic cable support hardware, toprovide total distribution frames and main equipment room wiring between floors between the main distribution frames routing. Common medium is multi-cores cable and optical fiber cable twisted-pair.5.Equipment room subsystemThis subsystem is mainly from the devices in the cable, connectors and related hardware support, the role of the computer, PBX, cameras, monitors and other weak and connected to the interconnection of equipment up on the main distribution frame. Equipment includes computer systems, network hub (Hub), network switches (Switch), program-controlled switchboards (PBX), audio output devices, CCTV control devices and alarm control center, etc.6 Buildings subsystem (Campus):The subsystem will be extended to cable a building complex of other buildings of the communications equipment and devices, is part of a structured cabling system to support the provision of buildings in the hardware required for communication between. It consists of cables, fiber optic cable and into the Building Department, over-current over-voltage protection equipment and other related electrical hardware, commonly used medium is optical fiber. Compared with the traditional routing, integrated wiring construction as a modern information transmission system, its main advantages are: Traditional wiring specification due to lack of a unified, user must choose a variety of different application types of cables, connectors and wiring, resulting in duplication of cable laying waste, lack of flexibility and can not support the development needs of the user application re-wiring; integrated wiring system integration requirements of modern architecture transmission of voice, data, video and other information, using international standardized information interface and performance specifications, to support multi-vendor equipment and protocols to meet the rapid development of modern enterprise information application needs.Integrated wiring system, the user can according to actual needs or changing office environment, flexible and convenient way to achieve change and restructuring routes, adjusting the mode of building the network required to fully meet user business needs.Structured cabling system is the star topology wiring methods and standard interfaces, which greatly improves over all network reliability and manageability, significantly reduce system management and maintenance costs. The modular system design to provide a good system scalability and future-oriented application development support, fully guaranteed the user's investment in cabling, providing customers a long-term benefits.Cabling System can solve the traditional wiring methods exist many problems, provides long-term benefits of advanced and reliable solutions. With the rapid development of modern information technology, integrated wiring system will be indispensable to modern intelligent building infrastructure.综合布线系统现代科技的进步使计算机及网络技术飞速发展，提供越来越强大的计算机处理能力和网络通信能力。

科技文献中英文对照翻译

Human Geomatics in Urban Design—Two Case Studies在城市设计中的人类地理信息学——两个案例研究Małgorzata Hanzl1,*,Karol Dzik2,Paulina Kowalczyk2,Krystian Kwieciński2,Ewa Stankiewicz2and AgataŁ.Wierzbicka2Abstract:The mapping of different aspects of urban phenomena and their relation to thephysical cityscape has been greatly extended by the use of geomatics.The tradition to basereasoning on‗understanding the world‘dates from the time of Aristotle.The extensionplan for Barcelona(Eixample),developed by Cerdà,which opened the era of modern urbanplanning,was preceded by analyses of rich data,describing both detailed demographicissues and physical structures.The contemporary,postmodernist city planning continuesthis tradition,although a shift towards analyses of more human-related issues can beobserved,covering,inter alia,citizens‘perception,cultural differences and patterns ofhuman activities with regard to distinct social groups.The change towards a morehuman-related perspective and the inclusion of urban morphology analyses are directconsequences of this trend.The required data may be gathered within a crowd-sourcingparticipation process.According to communicative planning theory,communication withthe wider public is indispensable in order to achieve the best results,and can be realizedwith the use of sophisticated IT tools.Evidence-based reasoning may be supported byimages of significant aesthetic values,which inspire immediate reactions.Keywords:GIS;crowd-sourcing;mash-up;education;urban planning;urban analyses摘要：不同方面的城市现象及其与物理城市景观的关系映射经由地理信息学的使用已经大大扩展了。

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13.3.3 C类放大器在C类功率放大器中，栅的偏压设成使晶体管在小于一半的时间内导通。

因此，漏极电流是由周期性的一串脉冲构成的。

传统上用正弦的上面部分来近似这些脉冲以便于进行直接分析②。

特别是我们假设漏极电流具有如下的形式：式中，偏置值I DC类似于线性放大器中的偏置电流，它对于C类放大器实际上是负值。

自然，整个漏极电流i D心总是为正或为零。

也就是说，漏极电流在晶体管导通时是一段正弦波，而在晶体管截止时为零。

我们继续假设晶体管在任何时候的工作情况都像是一个电流源(高输出阻抗)③。

由于我们仍然有一个高Q值的输出振荡回路，所以在负载两端的电压基本上保持为正弦，因此漏极电压和漏极电流如图13.4所示。

在以下的推导中，不必担心能否重复所有的这些细节。

正如我们将要看到的，我们如何设计这样的放大器与这些公式本身的含义有显著的不同，所以重点要放在所得到的一般结论而不是一些具体细节上。

我们从求解漏极电流不为零时总的导通角开始。

为了简化得到这一答案所需要的步骤，我们首先用余弦而不是正弦来重新写出漏极电流的表达式：显然，这样做没有任何改变，因为时间原点总是任选的。

在经过这样的修改之后，电流脉冲就如图13．5所示。

使电流等于零并求出总的导通角2中得到：我们现在可以计算平均漏极电流为:在用I DC的表达式替换后得到:我们将很快用这个表达式来推导效率作为导通角函数的公式。

我们需要的另一个量是传送到负载的功率的一般表达式。

正如与B类放大器一样由于高Q值的振荡回路而被简化，所以我们只需要计算傅里叶级数中的基波项：利用我们通过负载的基波电流的表达式，我们可以很容易地推导出最大输出电压摆幅的公式：上式允许我们求解用V DD表示的电流irf:峰值漏极电流为irf与偏置项的和为：上式可简化为:对于固定的输出电压，当脉冲宽度减小至零时，峰值漏极电流接近无穷大。

利用我们刚刚推导的公式可以很容易地计算出漏极效率为：当导通角缩小至零时，效率接近100％。

虽然这看起来很有希望，但输出功率也同时趋向于零，这是因为在漏极电流越来越窄的长条波形中基波分量也在缩小，而且从峰值漏极电流的公式中很清楚地看出，随着导通角接近于零，C类放大器归一化的功率传递能力也接近于零。

所有这些综合考虑使得实际上只得到小于100％的效率，因为除了高效率之外我们一般还希望有一个合理数量的输出功率。

在进行了前面的推导之后，我们也许会很失望，即这些推导在设计C类功率放大器的实际过程中一般不会用得很多。

一个理由是对栅偏压几乎没有几种方便的选择，但零伏是一种特别方便的选择。

因此栅驱动信号分量要选择得足够大从而能产生所希望的输出功率，所以导通角和效率通常不是直接的设计参数，而只是选择零偏压及输出功率设计的结果。

另一个理由是所做的假设(例如正弦电流尖峰脉冲，晶体管的电流源特性)并不总能充分地满足以使我们可以在定量上相信这些公式。

同样，在进行推导中最主要的优点是建立起对设计非常有用的某些一般的直观感觉——主要是效率可以很高，但这是以减少功率传递能力、增益和线性度为代价的。

13.3.4 AB类放大器我们已经看到A类放大器在100％的时间里导通，B类放大器在50％的时间里导通，而C类放大器则在0和50％之间的某段时间内导通。

AB类放大器，正如从它的名字可以联想到的，是在一个周期的50％和100％之间的某段时间内导通，这取决于所选择的偏置大小。

结果它的效率和线性度在A类和B类放大器之间。

这一折中常常是令人满意的，这从这类功率放大器的使用非常普遍就可以看出。

我们不必单独推导这一放大器的公式，因为C类放大器的公式也可以在这里应用(这些公式也包括A类和B类的情形)，惟一的差别就是偏置电流是正值而不是负值。

13.4 D类放大器至今介绍的功率放大器采用了有源器件作为控制电流源。

另一种方法是采用器件作为开关，其理由是，开关在理想上不消牦任何功率，因为或者开关两端的电压为零，或者通过它的电流为零。

因而开关的V-I乘积总是为零，所以晶体管不消耗任何功率并且其效率必定为100％。

利用这一想法的一类放大器是D类放大器。

初看起来(见图13.6)，它好像就是一个推挽式、变压器耦合的B类放大器。

与我们通常见到的并联振荡槽路不同，在这一放大器的输出端采用了一个串联的RLC网络，这是因为开关模式的放大器与前面学习过的电流模式的放大器相对偶，所以输出滤波器也互为对偶。

输入的连接方式保证了在一给定时间只有一个晶体管被驱动，其中一个晶体管在正半周工作而另一个在负半周工作，就像在推拉式B类放大器中那样。

这里所不同的是晶体管被充分驱动使它们的工作如同开关而不是如同线性(或准线性)放大器。

由于开关作用，输出变压器T2的每个初级终端被交替地驱动至地，从而在初级绕组(因而正在次级)两端产生一个方波电压。

当一个(晶体管的)漏极为零伏时，变压器的作用使另一个(晶体管的)漏极电压为2V DD。

输出滤波器则只允许这一方波的基波分量流人到负载中。

由于在次级电路中只有基波电流，所以初级电流也是正弦的，因此每个开关在它导通的半周期中见到的是一个正弦波，所以变压器的电流和电压如图13.7和图13．8所示。

由于晶体管的作用如同开关，所以D类放大器的理论效率为100％。

这个放大器归一化的功率传递能力即为①：它比B类推拉放大器要好，并且比A类放大器要好得多。

当然，D类放大器通常不能提供线性调制，但它却有可能提供高效率并且不会对器件产生过高的电压或电流。

这类(或任何其他开关)功率放大器的一个实际问题是并没有像理想开关这样的部件。

在开关过程中非零的饱和电压肯定会产生静态功耗，而有限的开关速度也意味着开关的V-I积在过渡期间不为零。

因此，开关模式的功率放大器只有在频率明显低于f r的情况下才能很好地工作。

而且，如果应用双极型晶体管由于晶体管在饱和区的电荷存储使一个晶体管导通之前另一个晶体管于能完全关断，那么效率的降低就会特别严重。

于是变压器的作用就会使全部电源电压加在还没有关断的器件上，从而V-I的乘积可能非常大。

13.5 E类放大器正如我们已经看到的，采用晶体管作为开关有可能提供大为改善的效率，但由于现实开关的不完全理想使得在实际中实现这一可能性并不总是那么容易。

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